Phylogenetic relationships of Marmosops Matschie, 1916 in the Atlantic Forest and topography effects on the diversity of M. paulensis Tate, 1931 (Didelphidae: Thylamyini)
摘要
Species from mountainous regions have a unique response to climate change, especially those that emerged at the end of the Quaternary. Montane formations have been considered stable zones for cold-adapted species during interglacial periods, extending species distributions during colder periods. The two sympatric and congeneric marsupial species, M. incanus and M. paulensis, have distinct patterns of distribution in altitude gradients in the Atlantic Forest, and both show large intraspecific genetic divergence and well-defined geographic groups. We showed the phylogeny of Marmosops species from Atlantic Forest and investigate the role of altitude in the genetic divergence of M. paulensis based on the mitochondrial cytochrome b gene sequences. The phylogenetic analysis showed isolate clades for M. paulensis populations from Mantiqueira and Serra do Mar chains. The lineages that give origin to the clades of M. paulensis emerged in the Pliocene (coinciding with the formations of Serra do Mar and Mantiqueira dated from Miocene and Pliocene epochs). The diversification patterns of M. paulensis were apparently driven by vicariant events during climate fluctuations in the Quaternary, agreeing with the performance of upper-mountain glacial refuges.